docs: def load_from_tar_or_patch(tar, image_filename, patch_images):
      """Do everything necessary to process an image inside a TAR.
  
      Parameters
      ----------
      tar : `TarFile` instance
          The tar from which to read `image_filename`.
      image_filename : str
          Fully-qualified path inside of `tar` from which to read an
          image file.
      patch_images : dict
          A dictionary containing filenames (without path) of replacements
          to be substituted in place of the version of the same file found
          in `tar`.
  
      Returns
      -------
      image_data : bytes
          The JPEG bytes representing either the image from the TAR archive
          or its replacement from the patch dictionary.
      patched : bool
          True if the image was retrieved from the patch dictionary. False
          if it was retrieved from the TAR file.
  
      """
      patched = True
      image_bytes = patch_images.get(os.path.basename(image_filename), None)
      if image_bytes is None:
          patched = False
          try:
              image_bytes = tar.extractfile(image_filename).read()
              numpy.array(Image.open(io.BytesIO(image_bytes)))
          except (IOError, OSError):
              with gzip.GzipFile(fileobj=tar.extractfile(image_filename)) as gz:
                  image_bytes = gz.read()
                  numpy.array(Image.open(io.BytesIO(image_bytes)))
      return image_bytes, patched